With the increasingly vigorous development of electronic goods market, the demand for liquid crystal display panels is also growing. This demand is caused because many electronic products use liquid crystal display devices (LCDs), such as TV screens, computer screens, and mobile phone screens. At present, a-Si TFT-LCDs have been replaced by LTPS TFT-LCDs. The LIPS technology has the advantage of high electron mobility, and is thus very suitable for the production of high-resolution display devices. However, a current LIPS process includes more than 10 procedures, far more complex than an a-Si process, and costs are also correspondingly increased. Therefore, it is very important to obtain a working state of a whole panel after an array substrate is manufactured. In addition, it is also essential to measure output of a gate on array (GOA) after the array substrate is manufactured due to wide application of a design of the GOA.
A plurality of detection steps is necessary before the LCD panel is lit. However, even after multi-detection, there is still a situation that some liquid crystal display panels cannot be lit. In this regard, destructive testing will be necessary for the array substrate of the liquid crystal display panel. An output waveform of the GOA is measured to find the problem, so as to avoid reoccurrence of a same problem.
In the prior art, as shown in FIG. 1, a method of detecting an array substrate in a liquid crystal display panel which cannot be lit is mainly performed as follows. A gate line 11 and a test pad 12 in a GOA unit around a display region 13 are electrically connected to each other by means of an electrical lead 10, and the test pad 12 is used to test an output waveform of the gate line 11. In this test method, since the gate line 11 and the test pad 12 are directly connected together by the electrical lead 10, the GOA is susceptible to static electricity during a manufacturing procedure of the array substrate, and even electrostatic wound occurs. And during the display of the liquid crystal display panel, as the GOA is electrically connected to the test pad, the screen is easily affected by additional loads, thereby causing abnormal display of a picture. Therefore, it becomes a technical problem to be solved urgently as to what kind of circuit can be used to test the GOA, and meanwhile to prevent static electricity from affecting the GOA in the manufacturing procedure of the array substrate and prevent an additional load from exerting an effect in a display procedure of the array substrate.